Uniform, adherent, single phase samarium doped ceria films have been successfully deposited by spray pyrolysis technique for their application in solid oxide fuel cell. These films have been deposited at different substrate temperatures on glass substrate and subsequently heat treated in tube furnace. Effect of substrate temperature and annealing temperature on phase formation was studied with thermo-gravimetric analysis and differential temperature analysis, X-ray diffraction, scanning electron microscope, and energy dispersive X-ray analysis techniques. These studies showed the formation of single phase Ce0.8Sm0.2O1.9 films, at substrate temperature 400 degrees C and annealing temperature 550 degrees C. Electrical resistivity of the films, at room temperature was of the order of 10(7) Omega cm while at 400 degrees C it is found to be of the order of 10(1) Omega cm. This reveals the use of these films for making low temperature solid oxide fuel cells. (c) 2006 Elsevier B.V All rights reserved.